Coronavirus disease 2019 (COVID-19) is the official name given by the World Health Organization (WHO) to the disease caused by SARS-CoV-2 (formerly known as 2019-nCoV), the new coronavirus that surfaced in Wuhan, China in 2019 and spread around the globe. The WHO considers COVID-19 to be a pandemic, a disease outbreak that covers a wide geographic area and affects an exceptionally high proportion of people.
Knowledge about the spread and potential treatment of COVID-19 is rapidly evolving as scientists investigate the disease. There is still a lot to learn about how the virus spreads, and why some infected people have no symptoms at all—or experience only mild cold-like symptoms that resolve on their own. COVID-19 attacks the lungs, and researchers are also trying to understand why a significant minority of those infected have serious symptoms, sometimes leading to pneumonia and even death.
“There is still much to learn about how this pathogen is transmitted between individuals,” says Richard Martinello, MD, a Yale Medicine infectious diseases specialist and medical director of infection prevention at Yale New Haven Health. “Data is needed not only to better understand when those who become ill shed the virus, but also which body fluids contain the virus and how those may contaminate surfaces and even the air surrounding them.”